1. Field of the Invention
The present invention relates to an extensible linkage apparatus, and particularly to an extensible clasp for items including jewelry, such as bracelets.
2. Description of Related Art
Bracelets and like jewelry are typically worn on the wrist or ankle, and must include a mechanism to secure the jewelry piece in place. Typically, there are two ways to attach a jewelry piece such as a bracelet to the wrist or ankle. First, the jewelry piece may separate to enable it to be wrapped around the wrist or ankle, and in which case must include a clasp mechanism to attach the ends together and secure the jewelry piece so that it remains in place. Second, the jewelry piece remains intact but is extensible so that it extends or expands to enable it to slide over the hand or foot, and then contracts to remain in place on the wrist or ankle.
Clasps can be difficult to use especially for jewelry worn on the wrist as the clasp must be operated with one hand. Some users have difficulty with manual dexterity and may find any clasp difficult to operate.
Examples of extensible bracelets include U.S. Pat. Nos. 839,538 and 2,718,750. The disclosure of these patents limit the possible physical structure of the bracelets to that which can accommodate the extensible features disclosed therein. In both cases, the extensible mechanisms are disposed within the bracelets.
U.S. Pat. No. 2,747,779 includes both extensible features and a separate clasp of a bracelet watch band. The clasp includes the problems mentioned above, and the extensible features are disposed within the band, thereby incorporating the disadvantages of both mechanisms.
There exists a need for a mechanism for use on a jewelry item such as a bracelet that provides ease of use and effectively retains the bracelet upon the wrist or ankle without limiting the structure of the bracelet to one that incorporates extensible features therein.